He's had failures before. But this line seems unfair. He was neither the first person in electric cars (a few notable failures before him) nor in rockets (e.g. Boeing)... but he was able to lead a team that figured out some of the key tech and the business models to make these things viable. Even with a lot of money, this is no small feat.
Unfortunately we will never know how much Musk contributed to any of these companies.
It is in his best interest to act like he was vital but unless you were there, there isn’t any way to know.
A guy with a vision and a few hundred million, in this context, has what many would have said would be a 0% chance of success. Many people somehow seem to have this view that if you just have enough money you can solve any problem in existence. It's probably just the consumerist mindset taken to its [not so] logical extremes - where literally anything is for sale, even that which doesn't exist.
I don't think he had some nefarious plan to kick them out from the get go. Sometimes personalities and ideas just clash, as theirs obviously did.
And that is the fucking problem. More and more shit if coming up about him (latests I saw today was an 'expose' about his degree and maybe even being illegally in the country, which I don't know if it is true or not) but people seem to believe whatever shit comes out of his mouth over facts. Was he pard of the success in Tesla, yes. Was he a founder/started it? Absolutely fucking not. Was Tesla be able to succeed without the government tax credits/investments, absolutely fucking not. But now that it is in a good path, he even moved state to avoid that 'government' issues. He is a fucking liar and a psychopath, but because he has money, people keep gargling his balls like they taste like candy mixed with wild truffles.
(no clue for SpaceX as I truly don't know).